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Introduction: Starting in 2019, the Apollo Next Generation Sample Analysis (ANGSA) Program has enabled consortium studies of specially curated Apollo samples that were previously unstudied (or under studied). This began with unsealed core tube 73002 [1,2] that is the upper part of a station 3 double drive tube. More recently the program extended to the study of a variety of frozen Apollo 17 samples [3], as well as the gas extraction [4] and dissection [5] of 73001, the lower half of the station 3 double drive tube, that was sealed under vacuum on the Moon. In this abstract we will examine the role of X-ray Computed Tomography (XCT) during the preliminary examination process for sealed core 73001, including: (1) engineering scans to aid in understanding the gas extraction process, whole-core scanning prior to opening to inform extrusion and dissection work, and (3) individual particle scanning to characterize rock fragment lithologies for follow on studies. Methodology: Sample 73001 is a 33 cm long, 4 cm diameter regolith sample collected inside a drive tube (~1 mm aluminum walls). That drive tube was sealed inside a 0.5 mm thick stainless steel (SS) Core Sample Vacuum Container (CSVC). XCT scans for engineering purposes were done on the Nikon XTH 320 system at Johnson Space Center using the 225 kV multi-metal reflection source at 215 kV, 179 ?A, and a 38.49 ?m voxel size. Individual >4 mm particles separated from the core during processing (then triply sealed in Teflon bags) were also scanned at JSC using the 180 kV source at 90 kV, 33 ?A, and a 2.98 - 10.65 ?m voxel size. Whole-core scans were done at the University of Texas High-Resolution X-ray Computed Tomography Facility (UTCT) on the 225 kV reflection source on the North Star Imaging cabinet XCT system. These scans included: (1) a series of 9 overlapping super-resolution scans each covering a ~4 cm length of the tube at 190 kV, 180 µA, and a 12.9 µm voxel size and (2) a lower resolution continuous helical scan of the entire core at 190 kV, 180 µA, and a 51.8 µm voxel size. Progress and Results: Before piercing and extracting the gas from sample 73001, an XCT scan of the bottom portion of the CSVC was used to confirm the location of the Teflon cap on the inner drive tube, to ensure it was not accidentally pierced during gas extraction. Similarly, after piercing, the bottom and top portions of the CSVC were scanned in order to capture engineering knowledge about the results of the piercing process, as well as the metal knife edge vacuum seal (SS into In-Ag alloy). Both scans will provide constraints on future work of this type, particularly for samples collected during the Artemis mission. Another finding from these "engineering" scans was that the device in the drive tube that immobilizes the regolith (the keeper) was not seated in the tube properly. This meant that (1) the drive tube could not be removed from the CSVC for the trip to UTCT, and (2) the procedure for opening and extruding the drive tube had to be modified. Had either of these things not been known prior to opening the CSVC, it could have led to an inability to XCT scan the whole core at high resolution and/or potential disruption of the core stratigraphy during extrusion. At UTCT, the entire length of the core was scanned at high resolution (12.9 microns per voxel). This scan serves multiple purposes: (1) A lower resolution (and uncorrected) version of these scans stitched together was used to help inform the processors of potential pitfalls during extrusion and dissection; and (2) the full resolution corrected data will serve as the permanent in situ record of the stratigraphy of the sample and will enable future researchers to perform a variety of analyses. So far, 92 of the 121 >4 mm particles separated during dissection pass 1 of sample 73001 have been individually scanned. These scans clearly show the lithology of each particle while keeping the particles in pristine condition. Because of the dust adhering to particle exteriors it would otherwise be impossible to determine lithologies in a non-contaminating way. Thus far the types of lithologies seen in sample 73001 (e.g., regolith breccias, impact-melt breccias, agglutinates, and basalts) are similar to those previously identified in sample 73002 [2]. By the time of the meeting, all particles from all 3 dissection passes will have been scanned and statistics on the different lithologies in 73001 compiled. [ABSTRACT FROM AUTHOR]

Introduction: A few weeks after their return to Earth, several Apollo 17 regolith sample splits and one Apollo 17 basalt were frozen at -20°C (under dry gaseous N2 like all other pristine Apollo samples), and have remained essentially unstudied within the Apollo sample collection at NASA's Johnson Space Center (JSC). As part of the Apollo Next Generation Sample Analysis (ANGSA) project, these frozen samples were selected for consortium study in 2019. Although the samples themselves were kept at -20°C for nearly 50 years, the JSC Curation office has lacked a facility for processing frozen samples under pristine Apollo processing conditions. A temporary lab for this work was designed, built, and tested [1]. Procedures were then developed for working in this unique environment, and the facility was successfully used to process the frozen Apollo samples for scientific allocation. Lab Design: An Apollo-era glovebox was cleaned and retrofitted to work within a -20°C environment, installed within a walk-in freezer within the experimental impact laboratory (EIL) at JSC (which itself underwent extensive upgrades and modifications), and plumbed for curation grade gaseous N2. A clean change room was also installed around the door to the freezer. For technical details on the project, see [1]. Operating Procedures: Cold weather gear was worn, including insulated pants, coat, a hat that covers the ears, and gloves or mittens. The person working inside the cabinet has to wear thinner gloves to allow for adequate fit and dexterity in the cabinet gloves. A clean lab smock, hair net, and nitrile gloves were then worn over the insulated clothing. Because the room was not ventilated, oxygen monitors had to be worn and actively monitored. For safety reasons, work could only proceed for up to 30 minutes at a time, a buddy system in the freezer was required, and a third person would stay outside to also monitor time and oxygen levels. The door opened periodically when leaving the room to exchange some of the air, and the windows on the cabinet had to be wiped down with isopropyl alcohol occasionally to remove frost buildup. Heat sealing couldn't be done inside the cabinet so the Teflon bags were sealed with clips and heat sealed in the anteroom as the samples were transferred out. Otherwise, sample processing was performed according to the same procedures and material limitations as the pristine Apollo sample labs. Results and Takeaways: The cold environment did not cause any noticeable difference in behavior of the samples during processing compared to working in nitrogen cabinets at room temperature. The biggest difference was the loss of dexterity from wearing insulated gloves inside polyurethane cabinet gloves that are stiff when cold. Wearing face masks turned out to greatly reduce the rate of frost buildup on the cabinet window. After completing the processing of these samples, this cold facility was dismantled, but our experiences here will be used when installing new permanent cold processing facilities in the Building 31 Annex, which should be up and running in a couple of years. [ABSTRACT FROM AUTHOR]

Introduction: Analyses of the samples returned by the Apollo Program have provided fundamental insights into the origin and history of the Earth-Moon system, and they have been used to place fundamental constraints on the origin and evolution of our Solar system broadly. After 50 years of curation, analysis, and study, our sophistication for handling and examining samples has greatly increased due to advancements in technology as well as the ability to build on previously attained knowledge. Some Apollo samples were collected or preserved in unique containers or environments and have remained unexamined by standard or advanced analytical approaches. The Apollo Next Generation Sample Analysis (ANGSA) initiative was designed to examine a subset of these special samples. The initiative was purposely designed to function as a new sample return mission with processing, preliminary examination, and analyses utilizing new and improved technologies and recent mission observations. The ANGSA initiative links the first generation of lunar explorers (Apollo) with future lunar explorers (Artemis). The teams involved in the ANGSA Program are examining two distinct types of samples: (1) Apollo 17 (A-17) double drive tube, consisting of an unopened vacuum sealed core sample (Core Sample Vacuum Container; CSVC 73001) and its unsealed but unstudied companion core 73002, (2) Apollo samples that were placed in cold storage approximately 1 month after their return in the early 1970s. Core samples 73001 and 73002 constitute the double drive tube core that penetrated a lunar landslide deposit in the Taurus-Littrow Valley. One of the Apollo goals for this double drive tube was to sample potential gases derived from the Lee-Lincoln scarp and trapped within the overlying landslide deposit. The total double drive tube core length is approximately 70 cm with 73001 representing the deeper part of the core. The temperature at the bottom of the core was approximately 250 K [1]. Sample 73001 was placed in a CSVC on the lunar surface and its upper companion core resided unexamined (until 11/2019) in a sealed aluminum double drive tube [2,3]. In addition to these sealed samples, the ANGSA Science Team is examining Apollo samples that were handled and curated at 253 K. Upon return, several A-17 soil splits, and vesicular high-Ti basalt (71036) were frozen at 253 K [2,3]. Progress and Results: In order to extract a potential gas phase from the CSVC 73001, the European Space Agency (ESA) designed, built, tested, and delivered to JSC a piercing tool. To collect and store the gas phase, Washington University of Saint Louis (WUStL) designed, built, and delivered to JSC a gas manifold system. Both of these instruments were integrated with the CSVC in early 2022, and gas was successfully extracted and preserved from both the outer and inner portions of the CSVC. The gas is undergoing basic characterization to determine whether a lunar component can be detected in the gas, and results should be completed before the 2022 MetSoc meeting. Following extraction of gas using the piercing and manifold tools, the lower part of the double drive tube (73001) was packaged in curation grade gaseous dry N2 (see [4]) and taken to UT Austin to be imaged by X-ray Computed Tomography (XCT). After XCT, the sample was brought back to the pristine core processing room in the Apollo curation lab at JSC for extrusion and dissection. We have completed the first dissection pass of 73001 and are preparing for pass two. Lithic clasts from pass one are being characterized by XCT at JSC. The cold curation facility for processing Apollo 17 frozen samples was completed and approved for use in mid-December 2021, and all samples were processed and allocated in early 2022. The cold-sample processing lab used for ANGSA was a temporary facility, but we are in the process of building a permanenet pristine cold-sample processing facility in the JSC Building 31 Annex, which should be complete in the next few years. [ABSTRACT FROM AUTHOR]

Introduction: Amidst the evolving field of lunar volatiles, there are debates regarding the abundances, distribution, and origin of volatiles in or on the Moon [e.g., 1]. Volatile elements and halogens (e.g., H, H2O, CO2, S, Cl, F) critically influence magma properties, dynamics, ascent, and eruptive processes. Basalts can record both the initial volatile composition of their parental melts, as well as subsequent volatile loss or addition (e.g., due to assimilation or degassing). Many lunar basaltic samples contain vesicles and vugs, which are important testaments to the gas-rich volcanic activity that occurred on the Moon. Coupling studies of degassing signatures, which are indirectly recorded in vesicles, with quantitative analyses of the volatiles within minerals can provide new insights to the chemical and physical evolution of lunar magmas. We investigate the magmatic, volcanic, and alteration histories of a suite of low-titanium and hightitanium lunar basalts using a novel combination of 2D analysis of textures, modal mineralogy, chemistry, and volatile abundances of rock thin sections, with 3D analysis of whole rock textures, modal mineralogy, and vug abundances and morphology. This work should elucidate the potential differences in eruptive characteristics between low-Ti and high-Ti lunar basalts. Samples: We are studying five low-Ti Apollo 15 basalts collected from the basaltic plain adjacent to Hadley Rille. Samples 15555 and 15556 are vesicular, olivine normative basalts; 15495 and 15499 are vuggy, porphyritic pigeonite basalts; and 15608 is an unusual basalt, which has not been previously investigated in detail. Additionally, we compare these low-Ti basalts to four high-Ti Apollo 17 basalts collected from Camelot Crater and the Central Valley: 75035 and 75055 (Type A basalts); 70215 (Type B); and 70035 (Type U) [e.g., 2]. Methods: To date, X-ray-elemental maps, backscattered-electron maps, and mineral chemical analyses of thin sections were acquired using the University of Arizona's Cameca SX100 electron microprobe and the NASA Johnson Space Center's (JSC) JEOL 7900F Scanning Electron Microscope. Mineral modal abundances were determined in 2D using thresholding [3] and quantified using ImageJ. These 2D abundances are compared to 3D XCT scans. For 3D analysis, XCT datasets were acquired using the NASA JSC Nikon XTH 320 instrument. The 3D modal mineralogy and vesiculation textures were determined through visualization and segmentation using Dragonfly™ and Blob3D software, respectively. Discussion: The 2D modal mineralogies calculated in this work agree with past studies that utilized point counting techniques [4,5]. These 2D modes will be compared to 3D values from XCT scans to evaluate sample heterogeneity. The analyses of apatite chemistry confirm the presence of fluorapatite, and the compositions overlap literature data reported for other Apollo 15 and 17 basalts [e.g., 1]. Pyroxene compositions indicate that basalt pairs 15555/15556 and 75035/75055, each likely derive from a similar parental magma [6]. However, 70215 was likely derived from a distinct parental magma [6]. Future chemical analyses will better constrain the origins of the remaining Apollo 15 and 17 basalts, and when coupled with XCT data, will elucidate the eruption sequences for the the low-Ti and high-Ti basalts. At the meeting we will present our chemical characterization, discuss our comparison of 2D and 3D data, and inform on the eruption sequences of the studied basalts. [ABSTRACT FROM AUTHOR]

Introduction: On April 27, 2022 at 8:03 a.m. CDT (1303 GMT) multiple eyewitnesses from Arkansas, Louisiana and Mississippi reported a bolide and sonic booms (AMS Event 2022-2591)[1]. NASA-Marshall Space Flight Center's Meteoroid Environment Office Lead Scientist Bill Cooke shared the event at 4:51p.m. on the NASA Meteor Watch Facebook Page. Cooke reported that the bolide was produced by a 40 kg object of approximately 0.3 meters in diameter, moving at approximately 56,327 kph. Observations show that the object broke apart roughly 34 miles above the ground. Late on the 28th, citizen scientist Eric Rasmussen contacted NASA- Johnson Space Center (NASA-JSC) scientist Marc Fries suggesting that there were very strong Doppler radar reflections near the time of the reported fireball. Fries posted his Doppler radar and dark flight model results on 29 April on the NASA-ARES website. On April 30, 2022 at 2:44 p.m., the first two meteorites were recovered 16.9km east of Natchez, MS on the shoulder (31°33'06.1"N 91°11'36.6"W) and median (31°33'08.9"N 91°11'25.9"W) of U.S. Hwy 84E. When officially confirmed, this meteorite will represent the fifth officially approved meteorite from Mississippi. It is the first recovered in MS since Tupelo (EL6 find) in 2012, and also the first fall in MS in 100 years, since the Baldwyn L6 chondrite fell in 1922. Strewnfield Model: Doppler radar returns. Weather radars (Fig. 1 top) in the NOAA NEXRAD network detected signatures of falling meteorites in eleven radar sweeps by four separate radars [2]. The first detection occurred 73 s after bolide terminus at an altitude of 11,257 m above sea level (ASL). The last detection occurred 358 s after terminus with detections occurring between 2,115 and 13,704 m ASL. Early strewnfield map. A strewnfield map was calculated using the Jörmungandr dark flight model (Fig. 1 top). Average mass in each radar sweep was estimated using change in altitude and time from the terminus. Masses range from 1.3 to 251g, with the caveat that larger masses commonly evade radar detection. The calculated strewn field estimates where meteorites of a given mass may lie, with the simpifying assumption that all meteorites originate from a common point at the terminus. The estimated strewn field and calculated landing sites for the radar signatures agree very well (Fig. 1 bottom). Preliminary Type Classification: The two stones, N1 (41.31g) (Fig. 2) and N2 (37.64g) (Fig. 3), were collected 30 April prior to 1 May rain, cleanly, using baked-out aluminium foil and bagged in Teflon for transport. The samples were weighed two days later at NASA-JSC, photographed and then measured for their magnetic susceptibility. The Log X value for N1 is 5.06 and for N2 is 5.08, suggesting that the stones fall in the range of values expected for L chondrites [3]. N2 is a broken stone revealing a matrix with clasts ranging from millimeters to centimeters in size. Clasts are poorly defined at margins, irregularly shaped and include a variety of textures suggesting that the meteorite represents a polymict breccia. Chondrules, when visible, are better preserved within clasts. The surrounding darker mottled matrix shows a wide range of millimeter-sized lighter colored irregularly shaped grains and chondrule fragments. Imagery of other stone fragments are also of mixed color and texture. XCT will be employed to characterize the range and degree of brecciation. Microprobe analyses are underway to confirm chemistry and petrology for a complete classification and subsequent submission to the Meteoritical Society Nomenclature committee. [ABSTRACT FROM AUTHOR]

Introduction: Apollo Sample 73001/2 is a ~71cm long double drive tube consisting of an upper part (73002) and a lower part (73001) that contains regolith collected near Lara Crater at the Apollo 17 site, Station 3. The double drive tube is believed to have penetrated a lunar landslide deposit that was transported from the slope of the South Massif into the Taurus-Littrow Valley [1]. As part of the ANGSA (Apollo Next Generation Sample Analyses) initiative, preparing a preliminary examination (PE) catalog of 73001/2 is a crucial first step for the early identification of material types such as rock fragments and potential stratigraphy within the core. Many new curation and scientific tools such as X-ray computed tomography (XCT) [3], multi-spectral imaging [4], and gas extraction manifold with piercing tool [5-7], have been applied to the ANGSA core to benefit curation strategy, PE efforts, sample allocation to the planetary science community, and ultimately help to prepare for future sample return missions like Artemis. 73001/2 Preliminary Examination and Processing: Sample 73002 was successfully opened and extruded in Nov. 2019 and fully dissected at the end of 2021. Sample 73001 (Fig. 1) was successfully extruded in March 2022 after careful planning before opening the Core Sample Vacuum Container (CSVC) that was holding the drive tube of 73001. XCT, as part of PE, was used to scan the bottom and top part of the 73001 core tube within the CSVC prior to opening it to 1) facilitate non-destructive, rapid detection of any contamination potentials due to piercing of the CSVC during gas extraction [7]; and 2) to aid in the Artemis sample tool development and provide data on the knife edge seal of the CSVC. This knowledge will help us connect the mechanics of the implemented design (i.e., XCT data) to the performance of the seal (i.e., data on the gas samples will tell us how well the seal preserved the volatile record of lunar samples). Both type of information will feed forward into Artemis tool and storage strategies for future samples. Results and Lessons learned: The XCT data of the CSVC and core tube within showed that the bottom Teflon cap was not pierced during gas extraction (Fig. 1c) and thus, the sample integrity remained guaranteed during piercing and subsequent gas extraction. However, the XCT scan of the top of the core (Fig. 1b) reveled that the drive tube was overfilled with lunar soil and the tool that keeps the soil constrained within the drive tube was not fully deployed. These preliminary data allowed us to implement the necessary steps to prevent loss of sample integrity, including any potential stratigraphy shifts during extrusion. Processing Apollo core 73001/2, creating an informative PE catalog, and applying new and refined tools and technologies for sample analyses are invaluable activities that will assist in circumventing any potential pitfalls, aid in the characterization of samples, and help in the assessment of how well any lunar material has been collected and preserved in the past. This will aid in designing future sample collections and curation procedures and help to prepare for future human exploration and sampling missions such as Artemis. [ABSTRACT FROM AUTHOR]